Ink cartridges for use in inkjet printers are often completely filled with ink during manufacturing such that little or no air is present within the cartridge. Recently, however, it has been proposed to offer for sale partially filled ink cartridges as a lower cost option for customers.
A potential problem with partially filled ink cartridges relates to changes in pressure after the cartridge has been put into use. For example, if the customer installs a partially filled ink cartridge into his or her printer and then transports that printer to a higher altitude location, the reduced atmospheric pressure of the higher altitude causes the air within the cartridge to expand. If that air cannot escape from the cartridge, it can apply pressure to the ink contained within the cartridge and cause that ink to leak or “drool” out of the cartridge.